arnold



(No Model.) 2 Sheets-Sheet 1. W T ARNOLD BURGLAR ALARM SYSTEM.

No. 587,669. Patented Aug. 3,1897.

Eve/7%)- WZZZZMYWI/MQ dfizvme es.

m: uonms mas o0. morn-mo. wunma'ron. I:v 1..

(No Model.) 2Sheets-$heet 2. W T ARNOLD BURGLAR ALARM SYSTEM.

Patented Aug. 3,1897.

liar/622%??- ZOzZ/zizigdgzofl Z /5 m dffarvzeyls.

. the armat-u res thereof.

UNITED STATES I PATENT OFFICE.

\VILLIAM T. ARNOLD, OF CIIICAGO, ILLINOIS, ASSIGNOR TO THE CHICAGO ELECTRIC PROTECTIVE COMPANY, OF SAME PLACE.

BURG LAR-ALARM SYSTEM.

SPECIFICATION forming part of Letters Patent No. 587,669, dated August 3, 1897. Application filed December 15, 1896. Serial No. 615,816. (No model.)

To all whom, it may concern:

Be it known that 1, WILLIAM T. ARNOLD, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Burglar-Alarm Systems, (Case No. 6,) of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to burglar-alarm systems, and has for its objects the provision of improved means for automatically testing the condition of the protectingcirc nits associated with guarded structures, and improved means at the central office for indicating abnormal changes in said protected circuits.

In a patentto Alfred Stromberg, No.477,712, issued June 28, 1892, is shown and described a burglar-alarm system in which a resistance is included in series between two sets of pro tecting-eonduetors. A battery and signal apparatus at the central office is normally included in circuit with the said protectingconductors, the aforesaid resistance serving to reduce the battery-current sufficiently to prevent the operation of the signal apparatus. A clockwork device is employed in this systern, one being located at each protected station, which is adapted to shunt this resistance at regular intervals, whereby the aforesaid signal apparatus is caused to operate. Each clockwork mechanism is under the control of the subscriber at the station where it is located.

One feature of my invention consists of devices for short-circuiting the aforesaid resistances, onelocated at each subscribers station, under control of apparatus at the central office, whereby accuracy of tests is assured.

Generally speaking, the preferred form of one feature of my improved burglar-alarm system comprises a round circuit includinga relay at each subscribers station, a resistance and main battery at the central office, and clockwork mechanism adapted to shunt said resistance at regular intervals, whereby the battery-current through the said relaysis increased sufficiently to cause the attraction of The armatu res of the relays at the different subscribers stations are thus simultaneously attracted, and upon being attracted shunt the artificial resistance between the protecting-conductors, whereby signal apparatus at the central office is operated.

\VhatI term govern or-relays are located at the central office, one being included in circuit with the protecting-conductors at each subscribers station and the aforesaid main battery. lVhen the resistance at the subscribers station is shunted as aforesaid, these governor-relays serve to operate visual signals. These governor-relays also serve to operate another set of signals, preferably both audible and visual, when any of the conductors become broken. 7 I

My invention will be more readily understood by reference to the accompanying drawings, in whicl1 Figure l is a diagrammatic view of a burglaralarm system embodying my invention.

Fig. 2 is a view in elevation of a governor-- relay that I prefer to employ in practicing my invention. Fig. 3 is a sectional view on line 3 3 of Fig. 2. Fig. 4 is a View in elevationof a visual signal which I prefer to employ, this signal being actuated upon the shunting of the artificial resistance of the corresponding subscribers station.

Like letters and figures refer to like parts throughout the different views.

Three subscribers stations 1, 2, and 3 are shown. Conductor a extends from the central otfice A to the station 1 andlincludes in' and 3 are each similarly provided with protecting-conductors a a artificial resistance a, armature a, and contact a The protecting-conductor a at station 2 is in circuit with aliue 0, extending from the subscribers station to the central oflice, the circuit being completed through conductor a and the common return I). The protectingconductor a at subscribers station 3 is included in circuit with a line d, extending from the subscribers station to'the central office, this circuit being completed by way of protecting-conductor a and the common return I).

Governor-relays e, f, and g are included in circuit with the lines a, c, and d, respectively, the common return I), conductorb, and main battery h serving to complete the circuits through the governor-relays, which are thus normally energized. The governor-relays are preferably constructed as shown in Figs. 2 and 3, in which two magnets e e are axially alined. Between the opposing poles of the magnets is provided an armature e pivoted at c this armature being preferably polarized and presenting, for example, a polarity of positive sign to the opposed poles of the electromagnets. Magnet 6 upon the left is Woun d to present a polarity of negative sign to the armature, while the magnet upon the right is wound to present a polarity of positive sign. The tendency of the armature, therefore, is to rotate in a contra-clockwise direction about its pivot.

In order to maintain the armature normally in a central position, which is desired in connection with the present system, I provide an adjustable rider 6, supported upon and located beneath the pivot or armature, and which is adapted to counteract the repelling and attractive forces exerted upon the armature by the electromagnets. If any of the conductors in circuit with the governor-relay should become broken,the magnets will be deenergized and the armature rotated upon its pivot by the rider 6 in a clockwise direction, the armature being brought into contact with the adjustable contact-anvil 6 hen the artificial resistance included in circuit with the governor-relay is shunted, the magnets will be increased in strength, whereby the attractive and repelling forces upon the armature are increased and the armature rotated in a contra-clockwise direction, causing contact between the armature and the adjustable contact-anvil e. A light spring 6 is impinged upon by the armature when it is swung to this position, this spring being thereby thrown into contact with the anvil a for the purpose hereinafter set forth.

I preferably provide permanent magnets e e", which serve to quickly return the armature to its central position, when the magnets e e are energized to their normal strength.

Parts of the governor-relays e, f; and g, similar to the parts shown in Figs. 2 and 3, are given similar letters of reference.

Visual signals 2', 7t, and Z are provided,which are under the control of the relays e, f, and g, respectively. These signals are operated by the arm atures of the governorrelays when they are swung in a contra-clockwise direction, this movement of the armature being efiected, as aforesaid, when the resistance at the subscribers stations is removed from circuit with the battery 7L and the governor-relays.

an armature k pivoted at 76 A screen k is provided with an aperture before which the target, carried upon the end of the armature and bearing the visual signal, is normallydisposed. The armature is preferably polarized, presenting, for example, a polarity of positive sign to the opposed poles of the magnet, the contiguous pole of the magnet upon the left being adapted to present a positive pole to the armature while the magnet upon the right presents a negative pole when said magnets are energized.

The rider k is provided to normally keep the armature in the angular position shown. When .the magnets are energized, the annature is thrown into the central position shown by dotted lines, a detent in the nature of a light spring carried upon a rod 7: engaging said armature to prevent its return to itsangular position.

The parts of visual signals 1', k, and Z, similar to the parts shown in Fig. 4, are given similar letters of reference.

Visual signals on, 'n, and 0 are controlled by the governor-relays e, f, and g, respectively, while the audible signalp is controlled by each of the governor-relays. These signals m, n, 0, and p are adapted to be operated by any of the governor-relays whendeenergized-as, for example, if a conductor in circuit with governor-relay e is broken signals m and 1) will be included in circuit with battery q, conductor q, armature e of relay 6, contact-anvil e of said relay, conductor (1 The manner in which the artificial re- 7o sistances at the subscribers stations are shortcircuited will be set forth hereinafter.

The visual signals are preferably constructed as shown more clearly in Fig. 4, in.which two axially alined magnets is k are provided, between which is centrally disposed switch (1 conductors g and g the signal m i will appear, and the signal 19 will sound.

A round circuit 1" is provided which includes a relay-magnet a at each subscribers station, relay 1" at the central oflice, battery h, resistance r, and relayr The resistance r is high enough to reduce the current of battery h sufficiently to prevent the attraction of armatures a a a by the magnets a a a.

A shunt is provided about the resistance r comprising the conductors s 5', spring 8 and a wheel 8 driven preferably by a clock-train.

This wheel is provided with teeth,one of which is adapted to engage the spring 5 at regular intervals, say once a minute, thereby com pletmg the shunt about the resistance T The short-circuiting relays at subscribers" tures and the contact-anvils 6 serving to operate the signals 1', k, and Z, whose targets are removed from the openings in the screen At the same time the terminals 8' and e of each governor-relay are simultaneously brought into contact, these terminals serving to close a normally open shunt-circuit about the audible signal t. This shunt includes the aforesaid terminals, conductor t, battery (1, conductor q,'thence through any of the armatures of the signals e, f, and g, connected with conductor q, and any of the conductors, including the signals 2', k, and Z, the shuntcircuit being completed by conductor t which includes the terminals 0 e If for any reason the short-circuiting relays at the subscribers stations should fail to cut out the artificial resistances m the corresponding governor-relay will fail to operate. For instance, if the short-circuiting relay at subscribers station 1 should fail to cut out the artificial resistance a the relay 6 will fail to operate and the armature thereof will remain in its central position. The shunt-circuit about the bell i will be opened at the terminals 6 e controlled by relay 6, the battery q being thereby included directly in circuit with signal t, which will sound and attract the operators attention. The target of signal 2', together with its supporting-armature, will remain in the position shown. The operator hearing the signal 25 then notices the visual signals and knows by the condition of signal t' that the trouble is located at subscribers station 1.

The rod 7o, supporting the springs k is attached to the armature of the electromagnet a, which is adapted to be included in a local circuit with the battery a, spring a, and wheel 5 The spring a is adapted to make contact with a tooth of the wheel 5 shortly after the engagement of the spring s 'with one of said teeth, whereby the armature of magnet u is attracted and the rod k partially rotated upon its pivot 10 the springs it being thus removed from engagement with the armatures k, which are caused to resume their angular positions by the weight 70 the Visual signals being thereby restored shortly after they are operated in consequence of the short-circuiting of resistance r Thus the artificial resistances at the subscribers station are periodically and simultaneously cut out of circuit, thereby causing the simultaneous appearance of the targets of the signals i, k, and Z, these operations taking place without the slightest attention from the operator unless any of the governor-magnets should fail in its work, when the audible signal i will be caused to respond to attract the operators attention. Heretofore a large amount of apparatus had to be constantly under the watchful care of the operator, which I am thus enabled to dispense with.

It will be understood that the conductors a, b, o, and cl, extending to the subscribers stations, are all led into the guarded structure at one point. Now if the burglar in entering should accidentally connect the conductors ca 1), b c, or Z) d the corresponding resistance a will be shunted and the signalt and the corresponding visual signal operated.

In practice 'I extend each round circuit through twenty five subscribers stations, each circuit having associated therewith a bank of twenty-five governor-relays and fifty visual signals, twenty-five of which, similar to signals t, 70, and Z, are adapted to indicate the short-circuiting of the artificial resistance at the subscribers stations, while the other twenty-five signals, similar to m, 7t, and 0, are adapted to indicate the opening of lines extending to the subscribers stations. round circuit is separate and distinct from the others. If either of the conductors a, b, 0,,or d should become connected with conductor r, the magnet r which is of high resistance, will become short-circuited, and the signal 0 included in a local circuit with battery o by the armature of said magnet when released.

I ground the conductor 0' preferably at to. If the conductor 1" should be grounded at any other point, as in the act of effecting an entry into the guarded structure, the magnet 0" would be short-circuited and signal to included in a local circuit with battery 10 by the armature of said magnet.

If the conductor 7" should be opened at any point, both the magnets r and r would be deenergized, whereby the signals '0 w will both be operated. I include an electromagnet 50 in the common return Z2, which is normally energized by the battery h. If the common return should be opened, or if a ground should be put upon the same, the armature of electromagnet a; will close a local circuit through the signal y and the battery 10 causing said signal to give an alarm.

It is clear that the details of the system of my invention may be somewhat modified without departing from the principles involved.

I have purposely omitted the description of minor details and the enumeration of many modifications which may be made without departing from the principles of my invention, because to set these forth at length would obscure rather than make clear the more essential features.

In the claims I speak of removing resistance in the sense of short-circuiting or otherwise completing a path of low resistance about the same.

Having, however, fullyset forth one manner of practicing my invention, I claim, and

Each

IIO

desire to secure by these Letters Patent, to-

gether with all such modifications as may be made by mere skill and with only the limitations expressed or by law implied, the following:

1. In a burglar-alarm system, the combinathe central office, with a resistance at the subscribers station in circuit with said conductors or apparatus, a relay at the subscribers station for removing said resistance, a source of electricity and a resistance at the central office in circuit with said relay, automatic means at the central office for removing said resistance periodically, and suitable indicating apparatus at the central office adapted to respond to a changein the circuit condition at the subscribers station, substantially as described.

2. In a burglar-alarm system, the combination of a plurality of subscribers stations each having protecting conductors or apparatus connected with the central oflice, with a resistance at each subscribers station in circuit with said conductor or apparatus, a relay at each subscribers station for removing said resistance, a round circuit extending from the central ofiice to the subscribers stations in which said relays are included, means at the central oflice connected with said round circuit forloperating said relays, and suitable indicating apparatus at the central office adapted to respond to a change in the circuit conditions at the subscribers stations, substantially as described.

3. In a burglar-alarm system, the combination of a plurality of subscribers stations each having protecting conductors or apparatus connected with the central office, with a resistan ce at each subscribers station in circuit with said conductors or apparatus, a relay at each subscribers station for removing said resistance from circuit with said conductors or apparatus,a round circuit extending from the central office to the subscribers stations and including said relays, a resistance and a source of electricity included in said round circuit, means at the central oflice for removing the latter resistance from the round circuit,and suitable indicating apparatus at the central ofiice adapted to respond upon a change in the circuit conditions at the subscribers stations, substantially as described.

4. In a burglar-alarm system, the combination of a plurality of subscribers stations each having protecting conductors or apparatus connected with the central ofl ice, with a resistance at each subscribers station, in circuit with said conductors or apparatus, a relay at each subscribers station for removing said resistance from circuit with said conductors or apparatus, around circuit extending from the central office to the subscribers stations and including said relays, automatic means connected with said round circuit adapted to periodically remove the latter resistances at the subscribers station from circuit with said conductors or apparatus, and suitable indicating apparatus adapted to respond to a change in the circuit condition at the subscribers station, substantially as described.

5. In a burglar-alarm system, the combination of a plurality of subscribers stations each having protecting conductors or apparatus connected with the central oifice, with a resistance at each subscribers station in circuit with said conductors or apparatus, a relay at each subscribers station for removing said resistance from circuit with said conductors or apparatus, a round circuit extending from the 1 tion of a plurality of subscribers stationjaf with protecting conductors or apparatus at each subscribers station connected with the central office, governor-relays at the central office, one corresponding to each subscriber, adapted to respond upon a change in the condition of the circuit at the subscribers stations, means for simultaneously changing the circuit condition at the subscribers stations whereby said governor-relays are simultaneously operated, an audible signal adapted to be operated by one of said relays, and means jointly controlled by said governor-relays for. preventing the operation of said audible signal, substantially as described.

7. In a burglar-alarm system, the combination of a plurality of subscribers stations, with protecting conductors or apparatus at each subscribers station connected with the central oflice, governor-relays at the central ofiiice, one corresponding to each subscriber. adapted to respond upon a change in the condition of the circuit at the subscribers stations, means for simultaneously changing the circuit condition at the subscribers stations whereby said governor-relays are simultaneously operated, and a signal jointly controlled by said relays, substantially as described.

S. In a burglar-alarm system, the combination of a plurality of subscribers stations with protecting conductors or apparatus at each subscribers station connected with the central oflice, governor-relays at the central ofiice, one corresponding to each subscriber adapted to respond upon a change in the condition of the circuits at the subscribers stations, means for simultaneously changing the circuit conditions at the subscribers stations whereby said governorde lays are simultaneously operated, an audible signal adapted to be operated by one of saidrelays, means jointly controlled by said governor-relays for preventing the operation of said signal, and visual signals, one associated with and controlled by each governor-relay, substantially as described. I

9. In a burglar-alarm system, the combination of a plurality of subscribers stations each having protecting conductors or ap ratus, governor-relays, one connected with each subscribers station, adapted to be operated upon a change in the circuit condition at the subscribers stations, an audible signal adapted to be operated by one of said govern or-relays, said governor-relays being jointly adapted when simultaneously actuated to prevent the operation of said audible signal,

means for simultaneously changing the condition at the subscribers stations, and visual signals operated by said governor-relays, one visual signal being associated with and controlled by each governor-relay, substantially as described. 7

10. In aburglar-alarm system,tl1 e combination of a plurality of subscribers stations each having protecting conductors o'r apparatus connected with the central oiiice, governorrelays, one in circuit with the apparatus at each subscribers station, an audible signal eluding said relays and extending to the cent'ral oflice, and automatic means at the central office connected with said round circuit adapted to periodically and simultaneously operate the relays at the subscribers stations, substantially as described.

ll. In aburglar-alarm syste1n,the combination of apl urality of subscribers stations each having protecting conductors or apparatus connected with the central office, governorrelays, one in circuit With the apparatus at each subscribers station, an audible signal adapted to be operated by one of said governor-relays, said governor-relays When actuated simultaneously being adapted to prevent the operation of said audible signal,visual signals, one controlled by each governor-relay, a resistance at each subscribers station in circuit with said protecting conductors or apparatus, a relay at each subscribcrfs station for removing said resistance, a round circuit including said relay and extending to the central office, a resistance and a source of electricity included in said round circuit, an automatic means for periodically removing said resistance from said round circuit, substantially as described.

12. In a burglar-alarm system ,the combination of a plurality of subscribers stations each having protecting conductors or apparatus connected with the central ofiice, signals as 1', 7c adapted to be actuated upon a change in the circuit condition at the subscribers stations, each of said signals having a movable element as 70 Which presents the signal, a rod 1& having springs or detents k supported thereon, said detents being adapted to engage said movable elements, an electromagnet to adapt- Ya signal device at the central office jointly controlled by the protecting apparatus at all of the subscribers stations and adapted, upon the failure of said means to change the circuit condition of the apparatus at any subsoribers station, to give a signal through the agency of the protecting apparatus at the remaining stations Whose conditions are changed, substantially as described.

In witness whereof I hereunto subscribe my name this 10th day of December, A. D. 1896.

IVILLIAM T. ARNOLD.

Witnesses:

A. L. LAWRENcE, GEORGE L. CRAGG. 

